Cutting and creasing dies



' Nov. 18, 1958 CUTTING AND CREASING DIES Filed Dec. 27, 1955 2 Sheets-Sheet l ii Mi ma AM ATTORNEY M. l. WILLIAMSON 2,869,555

INVENTOR. Marshall Williamson Nov. 18, 1958 M. l. WILLIAMSON 2,360,555

CUTTING AND CREASING DIES Filed Dec. 27, 1955 I 2 Sheets-Sheet g Fig. 6

INVENTOR. Marshall I Williamson BY W '5, W ATTORNEY United States Patent CUTTING AND CREASING DIES Marshall I. Williamson, New Haven, Conn.

Application December 27, 1955, Serial No. 555,432

4 *Claims. (Cl. 9358) This invention relates to improvements in .the construction of cutting and creasing dies. Cutting and creasing dies are used for cutting box blanks out of large sheets or rolls of board and comprise cutting knives defining the outline of the blank as well as the location of other cuts through the stock, and scoring rules which weaken the board in preparation of subsequent folding operations.

Cutting knives and scoring rules are flat or bent strips of sheet steel provided either with a sharp cutting edge or a rounded scoring edge, depending on their respective use.

According to one conventional procedure the cutting knives and the scoring rules of a die are assembled in upright position, with the cutting edge or the scoring edge pointing upward, the spaces between the various knives and rules being filled by blocks, of either wood or metal, called furniture in the box making art. A conventional cutting and creasing die is laid out by selecting available furniture, or manufacturing special furniture having the desired dimensions, placing the knives and rules between the furniture and then tightening the entire assembly by wedges, or otherwise, within a surrounding frame or chase. The above outlined procedure makes the accuracy of the box blanks dependent on the skill and the care of the diemaker.

According to another conventional procedure slots are cut into a large block .or panel of wood and thevknives and rules are placed .in these slots. This construction makes it necessary to discard the'entire die when a major dimensionof the box, such as length, width :or heightis changed.

It is often necessary to prepare'dies for limited production of sample boxes,.and not infrequently such sample boxes are of intricate construction involving many cuts, creases, dimensions and angles which-must the maintained within very close tolerances. so that the physical properties, as well as the appearance of the sample box :may be fairly judged by prospective customers. It may :also become necessary to prepare a series of sample boxes of identical basic construction, but ,of different sizes. Hollow walled boxes of the type disclosedinihe patents to Williamson, Nos. 2,605,953 and 2,605,954, dated August 5, 1952,:rnay be selected as :typical examples.

These boxes comprise a rather intricate corner construction which must be reproduced with :a high degree of accuracy in the samples. If, 'forreasons of comparison, boxes of different depth, and of different main-or bottom panel area must be prepared, it would be necessary, according to conventional diemaking practice, to 'lay out and build the intricate corner assembly of the die four timesfor each size.

It is easily seen that if such work is carried on in different parts of the country, by different diemakers, at about thesame time,.a great amount of diemaking work is involved as well as the multiplied danger of inaccuracies in the .die construction, more particularly where the reice cats only .two types of blocks are needed, the one {type being a mirror image of the other.

No problem is encountered in the manufacture of boxes of different main panel area since the change from one size to another is readily carried out by replacingcertain knives and rules by longer or shorter ones while leaving the corner blocks intact.

The invention also makes it possible to produce .boxes of different depth or ,angularity .of the side walls by re- .placing ,the corner blocks by others, without necessity of manufacturing new knives and rules for cutting and creasing the side walls and the end walls .of the box.

These and many .other advantages, objects ,and features of this invention will appear more fully from the detailed description which follows accompanied by drawings showing, for the purpose --of illustration, .a preferred embodiment of the invention.

The invention also resides in certain new and ,original features of construction and combination of elements hereinafter set forth and claimed.

Although the characteristic features of this invention which are believed to be novel will be particularlypointed out in the claims appended hereto, the invention itself, its objects and advantages, and the manner in which it may be carried out, maybe better understood by referring to the following description-taken in connection with the accompanying drawings forming apart ,of it, in which:

Figure l is a perspective view-of a die embodying v:the

invention, the die being raised to an angular position with ure 1;

Figure 3 is a perspective view of a box made from :the blank of Figure 2, the box being also raised to an angular position for more convenient illustration of details;

Figure 4 is a-perspective view of a, portion -,of the die of Figure 1, a part of the die portion being brokenlaway, to show details of construction;

Figure 5 is a perspective view of atypical cutting :knife for inter-connecting die blocks; and

Figure 61s a perspective view of the-typical internally fitted cutting knife. i

In the following description and :in the claims various details will be identified 1by specific names for convenience. The names, however, are intended-to'be generic in their application. Corresponding reference characters refer to corresponding parts in the several figures ;of the drawings.

The drawings accompanying, and forming a part of, this specification disclose certain specific ,details of the invention for the purpose of explanation of broader aspects of the invention, but it is understood that the details may be modified in various respects without departure from the principles of the invention and that the invention may be applied to other structures than the one .shown.

Referring to Figure 1, the illustrated form of cutting and creasing die comprises four corner blocks 11,12,13 and 14. These blocks may be made of wood preferably multi-ply hardwood, or they may bemade of metal, for example by die casting. The blocks comprise .a plurality of slits within which cutting knives and scoring rules are fitted.

The illustrated die is symmetrical and it is readily seen that corner blocks 11 and 14, as well as blocks 12 and 13, are identical.

Comparing blocks 11 and 12 it is readily seen that the configuration of block 12 is a mirror image of block 11.

In order to produce a die for a symmetrical box as represented by Figures 2 and 3 having inside dimensions W and L only two basic forms of corner blocks are required, namely blocks 11 and 12. Block 14 is identical in shape with block 11 and block 13 is identical in shape with block 12.

The four blocks are inter-connected by cutting knives and scoring rules of which groups 15 and 16 cut and crease the end wall assemblies 17 and 18 of the box, whereas two further groups 19 and 20 produce the side wall assemblies 21 and 22 of the box. The side wall assemblies and the end wall assemblies of the box are articulated to a bottom or main panel 23.

The corner assemblies of the box are comprehensively identified as assemblies 24, 25, 26 and 27 and are produced by correspondingly placed groups of knives and rules in the die blocks. The groups of knives which produce the corner assemblies are identified by numbers 28, 29, 30 and 31. For convenience of illustration, the blank of Figure 2 is shown in the position which it would assume, it it had been just lifted from the die.

In the manufacture of die samples it is the practice to place a sheet of board over the die and to pound the board with a mallet to produce the cuts and scores. The blank shown in Figure 2 therefore has its scores on the under-side.

Whereas the groups 15, 16, 19 and 20 of knives and rules extend from one block to another and may, for this reason, appropriately be called inter-connecting or external knives and rules,-the groups 28, 29, 30 and 31 may be termed internal knives and rules in that they terminate short of the boundaries of the respective block. Figure 4 illustrates the block 11 as it would appear after removal of the inter-connecting or external knives and rules. The group of internal knives and rules 28 is shown fitted in corresponding slots of the die block. These slots are alike in nature for internal knives and rules and for external knives and rules. They extend throughout the block from the top surface 32 to the bottom surface 33.

The slots which are shown at 34 for the group 19 of knives and rules, and the slots 35 for the group 17 of knives and rules for the end wall structure are interrupted at certain points to provide inter-connecting bridges 36 which connect portions of the block on opposite sides of the same slot. For convenience in manufacture, the interconnecting bridges are preferably bounded by holes 36 extending through the block. The presence of such holes in Figures 1 and 4 indicates the preferred location of the aforementioned bridges.

The inter-connecting knives and rules comprised in groups 15, 16, 19 and 20 are represented by knives 37 and 38 in Figure 4 and are shown as having notches 39 cut into them from the bottom edge of the knives. These notches straddle the inter-connecting bridges 36 and lock the corner blocks against end-wise displacement with respect to the inter-connecting knives and rules.

The internal knives and rules, of which knife 40 of Figure 6 is representative, are similarly notched to fit corresponding bridges in the die block, as is readily seen by referring to Figure 4 in which knife 40 is identified. For most internal knives and rules one notch 39 is sufficient. This is also seen by comparing the length l of the several knives and rules within the group 28 with the corresponding bridge-defining holes 36.

The height H of the knives md rules exceeds the thickness h of the die block so that the cutting edges of the knives and the rounded edges of the rules project an appropriate distance above the die blocks when the bottom edges 41 of the knives and rules are flush with the bottom surface 33 of the die blocks.

The illustrated die blocks define the height and angularity of the side walls 21 and 22 and the height and angularity of the end walls 17 and 18 of the box. These dimensions are set by the spacing of the parallel slots into which the groups of knives and rules 15, 16, 19 and 20 are fitted. The dimensions of height and angularity of the walls also determine the depth of the box.

It is readily apparent that neither the height, angularity of the walls nor the depth of the boxes is altered if the internal bottom area of the box, as represented by L, and W is increased or decreased. It is therefore possible to produce a larger or a smaller box simply by replacing the interconnecting knives and rules by longer or shorter ones. The end dimensions of the corresponding knives and rules, in other words, the distances from the notch 39 to the end of the rule remains the same, so that the new knife or rule after insertion into the die blocks properly abuts the internal knives and rules which produce the box corner. The distance L between the notches 39 is made greater or smaller in accordance with the size of the box to be produced.

If, on the other hand, it is desired to produce a series of boxes of identical bottom area 23, but of different angularity of the walls or of dilferent depth of the box, it is only necessary to replace the four corner blocks with their internal knives and rules, as represented by groups 28, 29, 30, 31. The inter-connecting knives and rules as represented by groups 15, 16, 19 and 20 may be reused in this instance, since, obviously, the scoring rules which produce the bounding crease lines of panel 23 remain the same, as long as the size of the panel 23 remains the same. Thus four sets of corner blocks and three sets of inter-connecting knives and rules make it possible to produce twelve difierent boxes.

Corner blocks for boxes of special design may be centrally produced by the same workmen or by the same machinery and may be shipped to different box makers with the corner assemblies 24, 25, 26 and 27 already fitted.

When it is desired to produce a box of certain size it is only necessary to insert the appropriate groups of inter-connecting knives and rules 15, 16, 19 and 20, an operation which may be performed by an unskilled person. If, on the other hand, boxes of the same main panel size but different depths or angularity of walls are to be produced, the appropriate corner blocks are selected and the appropriate groups of knives are inserted to produce a die for the box of the desired size. In all these operations the skill of the person assembling the inter-connecting knives and rules is of no influence on the accuracy of the resulting die. A die for a certain box may be produced within a matter of minutes, instead of within a matter of hours, and a degree of accuracy is obtained which is not equalled by the conventional diemaking procedure, even if carried out by highly skilled craftsmen.

What is claimed is: v

1. A self-contained cutting and creasing die for cutting and creasing a range of folding box blanks of different main panel area but the same depth, the die comprising a plurality of spaced blocks, there being at least one block for each corner of the box blank, said blocks having vertical slots therein adapted to receive cutting knives and creasing rules, certain portions of the slots extending entirely through the blocks, said slots being interrupted at other portions, so as to leave connecting bridges between the portions of the block on both sides of the respective slot; a first set of internal cutting knives and creasing rules in said blocks, the knives and rules of the first set terminating short of the boundaries of the respective block and representing a standardized configuration of the corners of the box blank; and a second set of interconnecting cutting knives and creasing rules abutting the ends of said internal knives and rules and extending from one block to another, said second set of knives and rules being replaceable by others of different lengths to produce a series of blanks of different main panel size, said second set of knives and rules having notches extending into said external knives and rules from the bottom edge and adjacent the ends, said notches fitting said bridges, therebyvlocking said blocks together at predetermined distances, said cutting knives and creasing rules being taller than the blocks to protrude above the top surfaces of the blocks when the bottom edges of the knives and rules lie flush with the bottom surfaces of the blocks.

2. A self-contained cutting and creasing die for producing folding box blanks having four box corner portions, the die comprising, four spaced corner blocks having substantially vertical slots therein, the slots within each block corresponding to the cuts and creases in a corner portion of the blank to be produced, certain portions of the slots extending entirely through the block from top to bottom, said slots being interrupted at other portions, so as to leave connecting bridges between the portions of the block on both sides of the respective slot; a first set of internal cutting knives and creasing rules in said corner blocks, the knives and rules of said first set terminating short of the sides of the corner block; and a second set of interconnecting cutting knives and creasing rules extending in substantially abutting relationship from the end of an internal knife and rule, respectively, in one block to an end of an internal knife and rule, respectively, in a spaced block, said cutting knives and creasing rules having notches extending into the knives and rules from their respective bottom edges, the notched portions of the knives and rules being seated in said slots to engage said connecting bridges, said cutting knives and creasing rules being taller than the blocks to protrude above the top surfaces of the blocks when the bottom edges of the knives and rules lie flush with the bottom surfaces of the block, said external connecting knives and rules engaging connecting bridges of the blocks between which they extend to lock the four corner blocks together as a unit.

3. A self-contained cutting and creasing die for pro inserted with their ends into slots of two spaced blocks,

said interconnecting knives and rules having notches extending from their respective bottom edges, the notched portion of the knives and rules being seated in said slots to engage said connecting ridges, thereby locking the four corner blocks together as a unit, the knives and rules of each set being of equal length and so positioned that their ends terminate at a line extending at right angles to the knives and rules; and a further set of internal cutting knives and rules terminating short of the sides of the block and abutting the ends of the interconnecting rules and knives, said internal knives and rules also having notches extending into them from their respective bottom edges, said last named notches engaging further connecting ridges in said blocks, the interconnecting as well as the internal knives and rules being taller than the blocks to protrude above the top surfaces of the blocks when the bottom edges of the knives and ruleslie flush with the bottom surfaces of the blocks.

4. A self-contained cutting and creasing die as set forth in claim 3 in which the slots in diagonally opposed blocks are of identical design so as to provide interchangeability of opposed blocks.

References Cited in the file of this patent UNITED STATES PATENTS 

